In Veneto, a 78-year-old man infected with the virus died, while a post-mortem on a 77-year-old woman in Lombardy came back positive, though it was not clear if illness from the virus caused her death.

The number of cases of people contracting the disease with no direct links to the origin of the outbreak abroad has been on the rise in the country.

Secondary contagions have prompted local authorities in Lombardy and Veneto to close schools, businesses and restaurants, with sporting events and Masses also being cancelled.

The mayor of Milan, Italy's business capital and the regional capital of Lombardy, shut public offices.

Veneto's regional president Luca Zaia explained that the contagion showed the virus is transmitted like any other flu and that trying to pinpoint a single source of infection or one with direct links to China is no longer effective.

He told reporters: "You can get it from anyone. We can expect to have cases of patients who had no contact with suspected carriers.

"While the virus isn't particularly lethal, it can be for the elderly or people with existing conditions."

An initial ordinance - penned by the health minister - imposed an effective cordon on 10 Lombardy towns around Lodi, southeast of Milan, after Lombardy reported a quadrupling of cases on Friday.

But individual cities outside that core cordon area, such as Cremona, issued their own restrictions and cancelled school after confirming their own cases.

The numbers of infected were in constant flux, but by Saturday had topped 25.